字幕列表 影片播放 列印英文字幕 In 2018, SpaceX will launch a new GPS satellite for the US Air Force. GPS has been vital for militaries, governments, businesses, and everyday navigation for decades. So who actually owns the Global Positioning System? Well, officially GPS was created, launched, and maintained by the United States, specifically by the Air Force Space Command. The idea originally came after Russia launched the first ever satellite, Sputnik. American scientists realized that they were able to calculate their position by interpreting the signal sent down from the satellite. Around the start of the Cold War, the US was secretly working on a way to increase the accuracy of their nuclear warheads, as a deterrent to the Soviet Union. By the 1980s, the positioning system was conceptually operational, but limited to military use. However, in 1983, a Korean Air Lines flight was shot down over Russia after accidentally entering prohibited airspace. The event galvanized both sides of the Cold War, and in an effort to avoid similar accidents from jeopardizing peace, President Ronald Reagan announced the existence of the Global Positioning System, and promised to make it available for civilians when it was fully up and running. About a decade later, in 1994, the first twenty-four satellites necessary for accurate coverage were launched, at the total expense of about 10 to 12 billion dollars, plus hundreds of millions of dollars a year in maintenance. Despite Reagan’s promise to make the system available to the public, civilians were limited to a weaker, and intentionally degraded signal, called “Selective Availability”. Until May 2000, this secondary signal assured the US military an advantage, in case an enemy were to use their own GPS against them. With the development of new technologies, this advantage soon became irrelevant, and President Bill Clinton removed the restrictions for civilians. Today, GPS is maintained by the US Department of Defense, and includes members from the Department of Homeland Security, the Joint Chiefs of Staff, and NASA. In fact, the DOD is required by law to maintain continuous, worldwide standard positioning services, due to its use in transportation, public safety, economy, science, timing, and especially “safety of life” navigation in the air and water. GPS’s operating cost is roughly estimated at 750 million dollars a year. But despite its ubiquity, the US isn’t the only country to run a global positioning system. Both India and Russia have also developed global positioning systems. Russia’s GLONASS system was developed around the same time as GPS, however it did not manage to reach the same level of global coverage until roughly a decade after the US’s system. It is primarily used by the Russian military, and today actually provides a more accurate reading of about 2 to 3 meters, compared to GPS’s, at best, 3.5 meters. The Indian Regional Navigation Satellite System was only finished in 2016, and is not yet fully operational, and additionally only covers India and the surrounding regions, making it not nearly as useful as GLONASS or GPS. China, Japan, and the European Union are also developing similar systems, but are much farther behind. GPS is integral to many navigational systems we use around the world for both military and civilian purposes. Every country in the world can use GPS, free of charge; but ultimately, it is owned and operated exclusively by the United States. We can’t do episodes like this without help from our sponsors like Domain DOT COM. Join millions of others online with your DOT COM or DOT NET domain name. Be recognized with the world’s premier web addresses. And our friends at DOMAIN DOT COM is giving fans 20% off domain names and web hosting when you use coupon code SEEKER at checkout. Pretty much everyone who owns a smartphone has access to GPS, but how exactly does it track your location? Find out in this video from DNews! Thanks for watching Seeker Daily. Make sure to like and subscribe for new videos every day.
B1 中級 有人真的擁有GPS嗎? (Does Someone Actually Own GPS?) 41 3 gotony5614.me97 發佈於 2021 年 01 月 14 日 更多分享 分享 收藏 回報 影片單字